definitions + formulas

Question 1

physical quantity

Answer 1

quantity that can be measured, consisting of numerical magnitude and unit

Question 2

scalar quantity

Answer 2

physical quantities that have magnitude only

Question 3

vector quantity

Answer 3

physical quantities that have both magnitude an direction

Question 4

speed

Answer 4

distance moved per unit time

Question 5

velocity

Answer 5

rate of change of displacement

Question 6

acceleration

Answer 6

rate of change of velocity
A = final velocity - initial velocity / time taken

Question 7

G

Answer 7

giga
1x10^9

Question 8

M

Answer 8

mega
1x10^6

Question 9

k

Answer 9

kilo
10^3

Question 10

d

Answer 10

deci
10^-1

Question 11

c

Answer 11

centi
10^-2

Question 12

m

Answer 12

milli
10^-3

Question 13

µ

Answer 13

micro
10^-6

Question 14

n

Answer 14

nano
10^-9

Question 15

Newton’s 1st Law

Answer 15

every object will continue in its state of rest or uniform motion in a straight line unless a resultant force acts on it (RF=0 -> _ - _ = 0)

Question 16

Newton’s 2nd Law

Answer 16

when resultant force acts on an object of a constant mass the object will accelerate in direction of resultant force (RF = ma)

Question 17

Newton’s 3rd Law

Answer 17

if body A exerts a force Fab on body B, body B will exert an equal and opposite force Fba on body A

Question 18

mass

Answer 18

amount of matter in a body

Question 19

weight

Answer 19

gravity acting on an object
W = mg
unit = N

Question 20

gravitational field

Answer 20

region in which a mass experiences a force due to gravitational attraction

Question 21

gravitational field strength

Answer 21

gravitational force acting per unit mass (Nkg^-1)

Question 22

what is inertia, with an example

Answer 22

reluctance of an object to change its state of rest or motion due to its mass (higher mass = higher inertia)

Question 23

density

Answer 23

density = mass/volume
unit is kgm^-3